The present invention relates to sanding devices in general and more particularly to sanding devices that are essentially dustless in use.
In plastering and drywall construction, a smooth finish generally is produced by sanding the surface. In drywall construction, for example, the abutting edges of the plasterboard sheets are covered with a paper or fabric tape and the sheets coated with a layer of plaster material. After the plaster material has dried, it is sanded until a continuous smooth surface results and the abutting edges no longer are discernible. The plastering and drywall construction operations generally are performed near the end of the construction project. Thus, it is important that the fine plaster dust removed by the sander be confined and collected so that the dust is not carried throughout the structure and does not settle on counter tops, walls which need to be painted or wallpapered, carpet or other flooring material, etc. The same concern is more acute when plastering needs to be conducted in the remodeling of an existing structure since furniture, dishes, wall hangings, and the like additionally need to be covered. Even when the room being refinished is sealed from the remaining interior space, the fine airborne dust readily penetrates the confinement and settles out through the remaining interior space.
A variety of techniques have been proposed in the art for connecting a source of suction (e.g. a vacuum cleaner) to the sanding device in order to confine and collect the dust created during the sanding operation. One such proposal found in U.S. Pat. No. 4,697,389 relies on a sand block disposed within the cavity formed by a shroud wherein the remaining annular space within the shroud is connected to a source of suction. In U.S. Pat. No. 4,062,152, an apertured solid plate is connected to a manifold which forms a vacuum chamber by virtue of a source of suction being connected to the chamber. In U.S. Pat. No. 4,759,155, a similar vacuum chamber is fitted with a plate having a pattern of grooves on its outer surface wherein a plurality of regular-occuring apertures are contained within the grooves and provide fluid communication to within the vacuum chamber. A mesh screen, for example, is fitted over the grooved plate and the source of suction engaged for confining the dust created from the sanding operation.
Despite the foregoing and other proposals in the art, no system aimed at substantially eliminating dust during sanding has found success in the marketplace. It is surmised that devices constructed in accordance with the principles employed in the foregoing prior art devices are limited in the fluid communication provided between the source of suction and the sanding screen. A substantial quantity of the dust created during the sanding operation thus is permitted to escape and contaminate the surrounding atmosphere. Thus, there is a long felt need in the carpentry, plastering, and drywall construction art for a dustless sanding device.